Azo dyes

ABSTRACT

Azo dyes of the general formula ##STR1## where A 1  is fluorine, chlorine, bromine, cyano, trifluoromethyl, C 1  -C 4  -alkylsulfonyl or substituted carbamoyl, 
     A 2  is hydrogen, chlorine, bromine or methyl, 
     A 3  is hydrogen, chlorine, bromine, carboxylic acid ester, cyano, trifluoromethyl, substituted carbamoyl, methyl, ethyl, methoxy or ethoxy, 
     A 4  is hydrogen, chlorine, methoxy or ethoxy, 
     R is hydrogen, hydroxy, amino, methyl, ethyl or propyl, 
     R 1  is hydrogen, substituted or unsubstituted C 1  -C 8  -alkyl, hydroxyl or amino and 
     X is cyano, carbamoyl or hydrogen. 
     The compounds according to the invention are outstandingly suitable for dyeing synthetic fibers, especially polyesters. The high tinctorial strength and the good fastness characteristics of the dyes deserve particular mention.

The present invention relates to compounds of the formula I ##STR2## where

A¹ is fluorine, chlorine, bromine, cyano, trifluoromethyl, C₁ -C₄ -alkylsulfonyl or substituted carbamoyl,

A² is hydrogen, chlorine, bromine or methyl,

A³ is hydrogen, chlorine, bromine, carboxylic acid ester, cyano, trifluoromethyl, substituted carbamoyl, methyl, ethyl, methoxy or ethoxy,

A⁴ is hydrogen, methyl, methoxy or ethoxy,

R is hydrogen, amino, methyl, ethyl or propyl,

R¹ is hydrogen, substituted or unsubstituted C₁ -C₈ -alkyl, hydroxyl or amino and

X is cyano, carbamoyl or hydrogen.

Examples of radicals A¹, in addition to those already mentioned, are methylsulfonyl, ethylsulfonyl, butylsulfonyl and radicals of the formula ##STR3## where R² and R³ are C₁ -C₈ -alkyl which may or may not be substituted by C₁ -C₄ -alkoxy, and R² may also be hydrogen.

Specific examples of carbamyl radicals A¹ (and also of A³) are: ##STR4##

Carboxylic acid ester groups A³ are in particular those of 1 to 8 carbon atoms, examples being: ##STR5##

Examples of substituted or unsubstituted alkyl radicals R¹ are alkyl radicals of 1 to 4 carbon atoms which may be substituted by C₁ -C₄ -alkoxy, alkanoylamino or alkoxycarbonylamino. Specific examples are: CH₃, C₂ H₅, n- and i-C₃ H₇, n- and i-C₄ H₉, C₂ H₄ OCH₃, C₂ H₄ OC₂ H₅, C₂ H₄ OC₃ H₇, C₂ H₄ OC₄ H₉, C₃ H₆ OCH₃, C₃ H₆ OC₂ H₅ and C₃ H₆ OC₄ H₉ and CH₂ NHCOCH₃, CH₂ NHCOCH₂ H₅, CH₂ NHCOC₃ H₇, CONHCOOCH₃, CH₂ NHCOOC₂ H₅, CH₂ NHCOOC₄ H₉ and ##STR6##

A compound of the formula I may be prepared by reacting a diazo compound of an amine of the formula II ##STR7## with a coupling component of the formula III ##STR8##

Details of the reactions may be found in the Examples, where parts and percentages are by weight, unless stated otherwise.

Compounds of particular importance are those of the formula I a ##STR9## where A¹ and A³ have the stated meanings.

The compounds of the formula I may be used for dyeing synthetic fibers, especially polyesters. They give orange to red dyeings distinguished by good fastness characteristics, eg. good lightfastness and fastness to dry heat pleating and setting. In certain cases, the tinctorial strength is very high.

EXAMPLE 1

9.3 parts of 4-chloro-4'-amino-azobenzene are dissolved in 100 parts of warm glacial acetic acid, the solution is then cooled to room temperature, 15 parts by volume of concentrated hydrochloric acid are added and the mixture is cooled to 10°-12° C. 14 parts by volume of a 23 percent strength aqueous sodium nitrite solution are then added at 10°-14° C. and the mixture is stirred for 21/2 hours at 10°-15° C. After destroying excess nitrous acid with amidosulfonic acid, the diazonium salt mixture is run into a solution prepared by heating 6.0 parts of 2,6-dihydroxy-3-cyano-4-methyl-pyridine in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution, and then cooling to 0° C. by adding ice. During the addition of the diazo component, sodium hydroxide solution is added to the coupling mixture so as to prevent the pH from falling below 4.5.

After completion of coupling, the mixture is heated at 80°-90° C. at pH 4.5-8 and the dye which has precipitated is filtered off as soon as the heat treatment has produced the desired crystal size, and is washed salt-free. After drying, 15.3 parts of a brown powder are obtained. The dye has the formula ##STR10## and dyes polyethylene terephthalate fabric, by the high temperature process (at 125°-140° C.), in deep orange hues having good lightfastness and fastness to dry heat pleating and setting. The dye is very economical in use.

EXAMPLE 2

8.9 parts of 4-cyano-4'-amino-azobenzene are diazotized by the method described in Example 1 and excess nitrous acid is destroyed. 6.6 parts of 1,4-dimethyl-2-hydroxy-3-cyanopyrid-6-one are dissolved in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution and are cooled to 0° C. with ice, after which the diazonium salt mixture is run in slowly, with thorough stirring, whilst keeping the pH at from 4.5 to about 9 by simultaneous addition of dilute sodium hydroxide solution. The coupling is completed rapidly. The suspension is heated to 70°-80° C. and is kept at this temperature for some time, and the dye which has precipitated is filtered off hot. After washing and drying, 15.5 parts of a reddish brown powder of the formula ##STR11## are obtained; this product dyes polyethylene terephthalate in orange hues having good lightfastness and fastness to dry heat pleating and setting.

EXAMPLE 3

9.8 parts of 4-chloro-3'-methyl-4'-amino-azobenzene are stirred into 50 parts by volume of glacial acetic acid. 2 parts of concentrated sulfuric acid are added, followed, at 10°-15° C., by 14 parts of a 42 percent strength nitrosylsulfuric acid solution. The diazotization mixture is stirred for 11/2 hours at 15° C. and after destroying the excess nitrous acid the mixture is combined with a solution of 5.5 parts of 2,6-dihydroxynicotinonitrile in 200 parts by volume of water and 4 parts of 50 percent strength sodium hydroxide solution, using a procedure similar to that described in Examples 1 and 2. After isolating the product in the conventional manner, 15.2 parts of a reddish brown powder of the formula ##STR12## are obtained; this product dyes polyethylene terephthalate fabric in reddish orange hues which are lightfast and fast to dry heat pleating and setting.

The dyes characterized in the Table below by specifying the substituents are also obtained by methods similar to that described above.

                                      TABLE 1                                      __________________________________________________________________________      ##STR13##                                                                     No.                                                                               A.sup.1         A.sup.2                                                                          A.sup.3                                                                               R.sup.1   Hue                                      __________________________________________________________________________     4  Cl              H H      CH.sub.3  orange                                   5  "               " "      C.sub.2 H.sub.5                                                                          "                                        6  "               " "      C.sub.3 H.sub.7 (n)                                                                      "                                        7  "               " "      C.sub.4 H.sub.9 (n)                                                                      "                                        8  "               " "      C.sub.4 H.sub.9 (i)                                                                      "                                        9  "               " "      CH.sub.2 CH.sub.2 OCH.sub.3                                                              "                                        10 "               " "      CH.sub.2 CH.sub.2 CH.sub.2 OCH.sub.3                                                     "                                        11 "               " CH.sub.3                                                                              CH.sub.3  "                                        12 "               Cl                                                                               H      C.sub.4 H.sub.9 (n)                                                                      "                                        13 "               " CH.sub.3                                                                              "         reddish                                                                        orange                                   14 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                                                   H H      CH.sub.3  orange                                   15 "               " CH.sub.3                                                                              "         reddish                                                                        orange                                   16 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                                                   H CH.sub.3                                                                              C.sub.2 H.sub.5                                                                          reddish                                                                        orange                                   17 "               " "      C.sub.4 H.sub.9 (n)                                                                      reddish                                                                        orange                                   18 "               Cl                                                                               "      "         red                                      19                                                                                 ##STR14##      H H      H         orange                                   20 "               " "      CH.sub.3  "                                        21 "               " "      C.sub.2 H.sub.5                                                                          "                                        22 "               " Cl     H         reddish                                                                        orange                                   23 "               " "      CH.sub.3  reddish                                                                        orange                                   24 "               " "      C.sub.2 H.sub.5                                                                          reddish                                                                        orange                                   25 "               " "      C.sub.4 H.sub.9 (n)                                                                      reddish                                                                        orange                                   26 "               " CH.sub.3                                                                              H         reddish                                                                        orange                                   27                                                                                 ##STR15##      H OCH.sub.3                                                                             H         red                                      28 "               " "      CH.sub.3  "                                        29 "               " "      C.sub.2 H.sub.5                                                                          "                                        30 "               " COOCH.sub.3                                                                           CH.sub.3  "                                        31                                                                                 ##STR16##      H COOCH.sub.3                                                                           C.sub.2 H.sub.5                                                                          "                                        32 "               " COOC.sub.2 H.sub.5                                                                    H         "                                        33 "               " "      CH.sub.3  "                                        34 "               " "      C.sub.2 H.sub.5                                                                          "                                        35 "               " "      C.sub.4 H.sub.9 (n)                                                                      "                                        36 C.sub.4 H.sub.9 (n)NHCO                                                                        " H      H         orange                                   37 "               " CH.sub.3                                                                              "         "                                        38 "               " H      CH.sub.3  "                                        39 "               " "      C.sub.2 H.sub.5                                                                          "                                        40 "               " "      C.sub.4 H.sub.9 (n)                                                                      "                                        41 "               " OCH.sub.3                                                                             CH.sub.3  red                                      42 "               Cl                                                                               H      H         orange                                   43 CH.sub.3 OCH.sub.2 CH.sub.2 CH.sub.2 NHCO                                                      H "      "         "                                        44 "               " "      CH.sub.3  "                                        45 "               " "      C.sub.2 H.sub.5                                                                          "                                        46 "               " CH.sub.3                                                                              H         "                                        47 CH.sub.3 OCH.sub.2 CH.sub.2 CH.sub.2 NHCO                                                      H CH.sub.3                                                                              CH.sub.3  "                                        48 "               " "      C.sub.4 H.sub.9 (n)                                                                      "                                        49 "               Cl                                                                               "      H         "                                        50 CH.sub.3 OCH.sub.2 CH.sub.2 NHCO                                                               H H      C.sub.4 H.sub.9 (n)                                                                      "                                        51 "               Cl                                                                               "      "         "                                        52 "               " "      CH.sub.3  "                                        53 "               " "      H         "                                        54 "               " CH.sub.3                                                                              "         "                                        55 C.sub.6 H.sub.13 (n)NHCO                                                                       H "      CH.sub.3  "                                        56 "               " "      CH.sub.2 CH.sub. 2 OCH.sub.3                                                             "                                        57 (i)C.sub.8 H.sub.17 NHCO                                                                       " H      H         "                                        58 "               " "      CH.sub.3  "                                        59 "               " Cl     H         red                                      60 "               " "      CH.sub.3  "                                        61 C.sub.2 H.sub.5 NHCO                                                                           " COOC.sub.2 H.sub.3                                                                    "         "                                        62 C.sub.4 H.sub.9 (n)NHCO                                                                        " "      "         "                                        63 Br              H H      H         orange                                   64 Cl              " Cl     CH.sub.2 CH.sub.2 OCH.sub.3                                                              "                                        65 CH              " "      C.sub.4 H.sub.9 (n)                                                                      reddish                                                                        orange                                   66 C.sub.4 H.sub.9 (n)NHCO                                                                        Cl                                                                               "      "         reddish                                                                        orange                                   67 CH.sub.3 CH.sub.2 CH.sub.2 CH.sub.2 SO.sub.2                                                   H CF.sub.3                                                                              "         reddish                                                                        orange                                   68                                                                                 ##STR17##      " CN     CH.sub.3  reddish orange                           69 "               " "      H         reddish                                                                        orange                                   70                                                                                 ##STR18##      " H      "         orange                                   71 "               " "      CH.sub.3  "                                        72                                                                                 ##STR19##      " "      "         "                                        73                                                                                 ##STR20##      " "      H         "                                        74 "               " "      CH.sub.3  "                                        75 "               " CH.sub.3                                                                              H         reddish                                                                        orange                                   76 "               " H      C.sub.4 H.sub.9 (n)                                                                      orange                                   77 "               " CH.sub.3                                                                              "         reddish                                                                        orange                                   78 Cl              " CON(CH.sub.3).sub.2                                                                   H         reddish                                                                        orange                                   79 Cl              Cl                                                                               COH(CH.sub.3).sub.2                                                                   CH.sub.3  reddish                                                                        orange                                   80 "               " "      C.sub.4 H.sub.9 (n)                                                                      reddish                                                                        orange                                   81 "               H COH(C.sub.2 H.sub.5).sub.2                                                            H         reddish                                                                        orange                                   82 "               " "      C.sub.4 H.sub.9 (n)                                                                      reddish                                                                        orange                                   83 "               Cl                                                                               Cl     "         reddish                                                                        orange                                   84 H               Cl                                                                               H      H         orange                                   85 Cl              Cl                                                                               "      "         "                                        __________________________________________________________________________

                                      TABLE 2                                      __________________________________________________________________________      ##STR21##                                                                     No.                                                                               A.sup.1    A.sup.2                                                                           A.sup.3                                                                               A.sup.4                                                                           X    R    R.sup.1                                                                             Hue                                  __________________________________________________________________________     86 Cl         H  H      H  CN   CH.sub.3                                                                            H    orange                               87 "          "  "      "  "    "    CH.sub.3                                                                            "                                    88 "          "  C.sub.2 H.sub.5                                                                       "  "    "    H    orange                               89 "          Cl H      "  "    "    CH.sub.3                                                                            orange                               90 "          "  "      "  "    H    "    "                                    91 H          "  Cl     H  H    CH.sub.3                                                                            H    "                                    92 "          "  "      "  "    "    CH.sub.3                                                                            "                                    93 "          "  "      "  "    "    C.sub.4 H.sub.9 (n)                                                                 "                                    94 Cl         "  H      "  "    "    "    "                                    95 "          "  Cl     "  "    "    H    orange                               96 "          H  CH.sub.3                                                                              Cl CN   "    "    reddish                                                                        orange                               97 Cl         H  H      H  CN   C.sub.2 H.sub.5                                                                     H    orange                               98 "          "  "      "  "    C.sub.3 H.sub.7 (n)                                                                 "    orange                               99 "          "  CON(C.sub.2 H.sub.5).sub.2                                                            "  "    CH.sub.3                                                                            C.sub.2 H.sub.5                                                                     "                                    100                                                                               "          "  "      "  "    C.sub.2 H.sub.5                                                                     CH.sub.3                                                                            "                                    101                                                                               "          "  "      Cl "    CH.sub.3                                                                            C.sub.4 H.sub.9 (n)                                                                 "                                    102                                                                               CH.sub.3 (CH.sub.2).sub.3 SO.sub..sub.2                                                   Cl "      H  "    "    "    "                                    103                                                                               "          "  CH.sub.3                                                                              "  "    "    "    reddish                                                                        orange                               104                                                                                ##STR22## H  H      "  CN   "    H    orange                               105                                                                               "          "  CN     "  H    "    C.sub.4 H.sub.9 (n)                                                                 "                                    106                                                                                ##STR23## "  H      "  CN   "    "    "                                    107                                                                                ##STR24## "  CH.sub.3                                                                              "  "    "    "    "                                    108                                                                               Cl         "  "      CH.sub.3                                                                          CONH.sub.2                                                                          "    "    "                                    109                                                                               "          Cl Cl     H  "    "    H    reddish                                                                        orange                               110                                                                                ##STR25## H  Cl     H  CONH.sub.2                                                                          CH.sub.3                                                                            C.sub.2 H.sub.5                                                                     orange                               111                                                                               Br         "  H      "  CN   "    H    orange                               112                                                                               Cl         "  COOC.sub.2 H.sub.5                                                                    "  "    "    C.sub.2 H.sub.5                                                                     reddish                                                                        orange                               113                                                                               Cl         CH.sub.3                                                                          H      H  CN   "    H    orange                               114                                                                               "          H  "      "  H    "    "    yellow                               115                                                                               "          CH.sub.3                                                                          "      "  CN   OH   "    "                                    116                                                                               "          H  "      "  "    "    CH.sub.3                                                                            "                                    117                                                                               "          "  "      "  "    NH.sub.2                                                                            H    "                                    118                                                                               "          "  "      "  "    "    CH.sub.3                                                                            "                                    119                                                                               "          CH.sub.3                                                                          "      "  "    "    "    "                                    120                                                                               "          "  "      "  "    "    H    "                                    __________________________________________________________________________

                                      TABLE 3                                      __________________________________________________________________________      ##STR26##                                                                     No.                                                                               A.sup.1     A.sup.2                                                                          A.sup.3       A.sup.4                                                                           R    R.sup.1                                                                             Hue                                __________________________________________________________________________     121                                                                               Cl          H H             H  C.sub.2 H.sub.5                                                                     H    orange                             122                                                                               "           " "             "  C.sub.3 H.sub.7 (n)                                                                 "    "                                  123                                                                               "           " CH.sub.3      CH.sub.3                                                                          CH.sub.3                                                                            C.sub.4 H.sub.9 (n)                                                                 reddish                                                                        orange                             124                                                                                ##STR27##  " "             "  "    "    reddish orange                     125                                                                               CH.sub.3 O(CH.sub.2).sub.3 NHCO                                                            " "             "  "    "    reddish                                                                        orange                             126                                                                               Cl          Cl                                                                               H             H  "    H    orange                             127                                                                               "           H CH.sub.3      Cl "    C.sub.4 H.sub.9 (n)                                                                 "                                  128                                                                               CH.sub.3 (CH.sub.2).sub.3 SO.sub.2                                                         H H             H  CH.sub.3                                                                            H    "                                  129                                                                               C.sub.4 H.sub.9 (n)NHCO                                                                    " "             CH.sub.3                                                                          "    "    "                                  130                                                                               "           " "             "  "    CH.sub.3                                                                            "                                  131                                                                               "           " "             "  "    C.sub.4 H.sub.9 (n)                                                                 "                                  132                                                                               Cl          Cl                                                                               COOC.sub.4 H.sub.9 (n)                                                                       H  "    "    "                                  133                                                                               "           " COOC.sub.2 H.sub.4 OCH.sub.3                                                                 "  "    "    "                                  134                                                                               "           H COOC.sub.2 H.sub.4 OC.sub.2 H.sub.4 OC.sub.4 H.sub.9                                         "n)                                                                               "    "    "                                  135                                                                                ##STR28##  " CN            "  "    "    reddish orange                     136                                                                               "           " "             "  "    C.sub.2 H.sub.5                                                                     reddish                                                                        orange                             137                                                                               Cl          " H             "  NH.sub.2                                                                            H    yellow                             138                                                                               "           " "             "  "    CH.sub.3                                                                            "                                  __________________________________________________________________________

                  Table 4                                                          ______________________________________                                          ##STR29##                                                                                                              Hue on                                No.  A.sup.1                                                                               A.sup.3  R     R.sup.1                                                                              X       polyester                             ______________________________________                                         139  H      H        CH.sub.3                                                                             H     H       golden                                                                         yellow                                140  "      "        H     "     "       golden                                                                         yellow                                141  "      OCH.sub.3                                                                               CH.sub.3                                                                             "     "       red                                   142  "      CH.sub.3 "     "     "       orange                                143  Cl     H        "     "     "       "                                     144  "      "        "     "     CONH.sub.2                                                                             "                                     145  H      "        "     "     "       "                                     146  "      "        NH.sub.2                                                                             CH.sub.3                                                                             CN      yellow                                147  "      OCH.sub.3                                                                               CH.sub.3                                                                             "     H       red                                   148  "      "        "     C.sub.2 H.sub.5                                                                      "       "                                     149  "      "        "     C.sub.3 H.sub.7                                                                      "       "                                     ______________________________________                                     

I claim:
 1. A dye of the formula ##STR30## A² is hydrogen or methyl, A³ is hydrogen, methyl or ethyl,X is hydrogen, cyano or carbamoyl and R¹ is hyrogen or C₁ - to C₈ -alkyl.
 2. A dye according to claim 1, wherein A² is hydrogen.
 3. A dye according to claim 1, wherein R¹ is hydrogen or C₁ - to C₄ -alkyl.
 4. A dye according to claim 1, wherein R¹ is hydrogen.
 5. A dye according to claim 1, wherein X is hydrogen.
 6. A dye according to claim 1, wherein A³ is hydrogen or methyl.
 7. A dye according to claim 1 of the formula ##STR31## wherein A³ is hydrogen or methyl,R² is hydrogen or C₁ - to C₄ -alkyl and X¹ is hydrogen or cyano.
 8. A dye according to claim 5, wherein R² and X¹ are hydrogen.
 9. The dyes according to claim 1 of the formula ##STR32## 